Volatiles produced by bacteria alleviate antagonistic effects of one associated fungus on Dendroctonus valens larvae

Dear Editor, Microbes play important roles in various symbiotic systems （Douglas, 2015; Xing et al., 2017; Zhu and Wu, 2016; Xu et al., 2016a）. In the symbiosis formed by bark beetles and microbial associates, beetles formed symbiotic relation- ships with some fungi including mutualistic and antagonistic ones （Cheng et al., 2015; Lu et al., 2016; Scott et al., 2008）, and these interactions, indirectly affected by a third or even fourth participator in a community context, may change from antagonistic ones to mutualistic ones. For example.